Membrane optics is a flat lens that employs plastic in place of glass to diffract rather than reflect or refract light.
Concentric microscopic grooves etched into the plastic provide the diffraction.
[1] According to DARPA, glass-based optics in satellites are reaching the point where larger mirrors exceed the lifting power of existing rockets.
MOIRE is planned to be one-seventh the weight of a comparable glass-mirrored device.
[1] A ground-based prototype consists of a section of a 5-meter (20 ft) wide device that created the first images with membrane optics.